A gasoline engine in a factory is fitted with an automatic

3. A gasoline engine in a factory is fitted with an automatic control
mechanism. Whenever the temperature of the engine's exhaust
increases, the flow of air to the engine is boosted . When more air
is introduced into the engine , fuel flow is increased into the
engine, fuel flow is increased to keep the air / fuel mixture is
constant. As more air and fuel are combusted , the engine's speed and
exhaust temperature both increase.

Which of the following can we expect from an engine with this control
mechanism?

a. The engine will oscillate between medium and low speeds.
b. The engine will not run continuously; the control mechanism will
automatically bring the engine to a stop.
c. The engine will accelerate to its maximum and possible speed and
stay there.
d. The engine will overheat within an hour of the engine's ignition.
e. The engine will oscillate between high and medium speeds.